In a situation where a MUIDataTable is nested within an expanded row, dragging columns from one MUIDataTable should only affect the selected table.
Dragging the columns of the outer MUIDataTable will cause the inner MUIDataTable's columns to move, too. Once the column is dropped, the correct column orders are present on both the inner and outer MUIDataTable.

See this sandbox: https://codesandbox.io/s/fervent-minsky-9eem8?file=/src/App.js
Try:
Once complete, the columns will be in the correct positions. It only looks strange when dragging the column.
| Tech | Version |
|--------------|---------|
| Material-UI | 4.11.0 |
| MUI-datatables | 3.1.5 |
| React | 16.13.1 |
| browser | Chromium |
I've released a beta version which should hopefully fix this issue:
npm install [email protected]
Codesandbox: https://codesandbox.io/s/hungry-dubinsky-wr1yu
Thanks! I can confirm that the beta version fixes the issue in my project.
Fixed in version 3.2.0.